The next time you have a ‘bad dive' because of lousy vis or dubious conditions, spare a thought for the commercial divers who have just ventured into Sellafield's 100-metre-long nuclear fuel storage pool for the first time in 65 years.
The nuclear power plant in Cumbria went out of use in the 1960s, and the pool was built in the 1940s for use by Windscale Piles, the site's first nuclear reactors, for the cooling, storage and de-canning of spent fuel as part of the UK's post-war atomic weapons programme. According to records, it was last entered back in 1958 to repair a broken winch, and now divers are back in the water with the rather unpleasant task of clearing sludge.
Josh Everett, a diver from the specialist US nuclear diving team Underwater Construction Corporation, was the first person to venture into the pool, dubbed ‘one of the most unique workplaces in the world'.
The divers get into the pool via a specially constructed access platform, and then position themselves on a metal dive stand with a shield floor. From there they work in shifts of up to three-and-a-half hours at a time to remove sludge and debris from the pool floor. Robots have been used in the past to remove the bulk of equipment from the pool, but the divers can get into hard-to-reach areas.
Once all of the waste material has been removed, the water will be drained out, ready for the final demolition of the building. The final decommissioning work is due to be completed by 2039, and has been estimated to cost around £212m.
Photo credit: Michael Lishman and Sellafield Ltd